Page MenuHomeFreeBSD
Differential D58501

uvideo: limit isochronous transfers to 32 frames
ClosedPublic
Actions

Authored by seuros on Jul 28 2026, 12:14 AM.
Tags
Referenced Files
Unknown Object (File)
Sat, Oct 10, 3:35 PM
Unknown Object (File)
Fri, Oct 9, 3:58 PM
Unknown Object (File)
Fri, Oct 9, 3:16 PM
Unknown Object (File)
Thu, Oct 8, 10:05 PM
Unknown Object (File)
Tue, Oct 6, 6:28 AM
Unknown Object (File)
Fri, Oct 2, 10:09 PM
Unknown Object (File)
Thu, Oct 1, 7:13 PM
Unknown Object (File)
Thu, Oct 1, 2:25 PM
View All 71 Files
Subscribers
None

Details

Reviewers
adrian
bapt
Commits
rGad9cc3f1da14: uvideo: limit isochronous transfers to 32 frames
Summary

Raising UVIDEO_NFRAMES_MAX from 40 to 128 in 3b6f833c95eb improved
throughput on xhci but made every camera on an ehci bus fail to
stream. Integrated webcams became unusable.

Measured on a MacBookPro9,2 with two ehci(4) FaceTime HD cameras and an
xhci(4) Logitech C920:

			  128		 32
  ehci, 12 captures	  0 ok		 12 ok
  xhci 1920x1080	  5 fps		  5 fps
  xhci 1280x720		 10 fps		 10 fps

Fixes: 3b6f833c95eb

Diff Detail

Repository
rG FreeBSD src repository
Lint
Lint Passed
Unit
No Test Coverage
Build Status
Buildable 75199
Build 72082: arc lint + arc unit

Revision Contents
Changeset List

PathSize
sys/
dev/
usb/
video/
2 lines

Diff 182874

View Options

sys/dev/usb/video/uvideo.h

Loading...